Is it possible to slice only one stl from the list in a 3mf project?  

RE: Is it possible to slice only one stl from the list in a 3mf project?

Yes, use the 'eye' icon in the right hand tree list to turn an object on/off when it comes time to slice.

RE: Is it possible to slice only one stl from the list in a 3mf project?

 I clicked with 2 fingers and the eye changed to crossed out. It allows me to turn objects on and off as you said.

I needed confidence to click until I found the right way.  Prior to this I couldn't get the eye to do anything.

Thank you very much.  Projects will be more useful to me now.

RE:

I had some 3mf files where all objects are visible as single model, so selecting/unselecting it was causing all models to show up/disappear. Not very convenient.

In that case you have few options:
- copy model as many times as there are models, for each separate copy add a negative volume over the objects you do not want to print, use hide/show icon to print only specific model - unfortunately this ends in pretty noisy view, where only sliced view shows cleanly what will be printed. This works okay for basic models, though.

- export model as stl and edit it in other tool - for example tinkercad via web browser and use negative volume to remove objects (create for example box with negative volume; holding CTRL key left click mouse to select multiple objects; when you have desired objects selected click merge, and it will substract negative model from the rest) and export such model into separate file, and reimport to 3mf files. This is a bit more time consuming but gives better separation and control of what you want to do or modify in the future.

RE: Is it possible to slice only one stl from the list in a 3mf project?

Alternatively use the split to Objects function. Many people don’t understand the fundamental difference between Objects and Parts in PRUSA Slicer.